Navigation aid for refreshable braille display and other text products for the vision impaired

ABSTRACT

A navigation aid for a refreshable Braille display and similar products for the visually impaired. A navigation wheel is located adjacent at least one end of the refreshable Braille display. Rotation of the wheel by an increment moves the displayed text forward or backward by a predetermined increment, such as by one word, or one line or one paragraph. In a preferred embodiment, the function performed by rotating the wheel can be changed by depressing the wheel. A separate navigation wheel may be located at opposite ends of the refreshable Braille display and the two navigation wheels may perform the same or different functions when rotated.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] Applicants claim priority to U.S. Provisional Patent ApplicationSerial No. 60/309,275 filed Aug. 1, 2001.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] Not Applicable.

TECHNICAL FIELD

[0003] The invention related to refreshable Braille displays for blindand low vision users, and more particularly for a navigation aid for arefreshable Braille display.

BACKGROUND OF THE INVENTION

[0004] For refreshable Braille displays, it has not been easy toposition the cursor for advancing displayed text by one word, or oneline, or one paragraph. For example, a Braille display user must movehis or her hands between the Braille display and the keyboard until thedesired cursor position is found. This can significantly slow thereading process. Frequently, the prior art navigation aids only allowmovement of the text or cursor by only one fixed step at a time, namely,by one word at a time. Consequently, scrolling through text can be timeconsuming.

[0005] U.S. Pat. No. 6,163,280 shows a Braille display having a row ofswitches above and a row of switches below the row of Braille cells. Theupper row of switches may, for example, position the displayed text andthe lower row of switches may position a mouse cursor within text to beedited. The switches are designed to be operated with the same fingerwhich is used to read the Braille cells. Consequently, the fingers mustbe moved from the displayed cell in order to operate the scrollingswitches. The user also must touch the display cells to determine theposition of the cursor.

[0006] Sliders provided with some refreshable Braille displays providenavigation speed, but have only a finite travel. Touching and moving afinger along the slider provides text navigation. For example, a sixinch slider could easily navigate through a page containing 25 lines oftext. Each line would require about one quarter inch of movement on theslider. But if the document has ten pages of text, each line wouldoccupy only about 0.024 inch movement. Consequently, some degree oftraining and skill may be required to precisely advance the text.

[0007] It is known that a computer mouse may have a programmablenavigation wheel. The navigation wheel has a mechanical detents. As thewheel is rotated between detents, a pulse is generated. It is known thatthe pulses may be used to advance the displayed text by a preselectednumber of lines. The navigation wheel also may be used to perform aprogrammed function when depressed, such as selecting a word orfunctioning as a double click of a mouse button. However, navigationwheels have not been used with Braille displays and the advantages ofusing a navigation wheel with a Braille display have not beenappreciated.

[0008] As used herein, “text products for the vision impaired” includesnot only refreshable Braille displays, but also notetakers, portablepersonal computer with a Braille display, and reading machines. A“notetaker” includes either a conventional keyboard or a Braillekeyboard for entering data, a memory for storing entered data, and anoutput device. The output device may be a Braille display, or it may bein the form of an audible output device including a program forconverting the stored text data to speech and either a speaker or anearphone for playing the speech. Or, the notetaker may include both aBraille display and an audible output. Vision impaired students, forexample, frequently use a notetakers for taking notes in the classroom.Later the notes may be read or listened to. The notes also may betransferred to a personal computer for reviewing, editing and storage.Some notetakers are capable of using replaceable memory cards. Text suchas a book may be stored on the card and the notetaker may be used forreading the text. Still another product for the vision impaired is thereading machine. Text such as a book may be stored on a tape, a CD or ina digital memory. The text is converted to audible speech. For each ofthese products, it has not been easy for a user to navigate or scrollthrough the text to a desired location.

BRIEF SUMMARY OF THE INVENTION

[0009] The invention is directed to a navigation aid for refreshableBraille displays and other text products for the vision impaired. TheBraille display consists of a row of cells for displaying individualtext characters. According to the invention, a rotary navigation wheelis located adjacent an end of the row of Braille cells and, preferably,a separate rotary navigation wheel is located adjacent each end of therow of Braille cells for navigating through text. Incremental rotationof the navigation wheel creates a pulse which moves the displayed textor a cursor either forward or backward, depending on the direction ofrotation. When navigation wheels are provided at opposite ends of therow of Braille cells, the two wheels may be programmed to provide thesame function or different functions.

[0010] Accordingly, it is an object of the invention to provide animproved navigation aid for refreshable Braille displays.

[0011] Other objects and advantages of the invention will becomeapparent from the following detailed description of the invention andthe accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012]FIG. 1 is a top plan view showing an exemplary keyboard of aBraille notetaker with a refreshable Braille display and including twonavigation wheels according to the invention;

[0013]FIG. 2 is a fragmentary cross sectional views showing details ofan exemplary navigation wheel and an attached encoder according to oneaspect of the invention;

[0014]FIG. 3 is a schematic circuit diagram illustrating the outputs ofthe encoder;

[0015]FIG. 4 is a graph illustrating the outputs of the two switches inthe encoder as the navigation wheel is rotated;

DETAILED DESCRIPTION OF THE INVENTION

[0016] The invention is directed to a navigation aid for refreshableBraille displays and other text products for the vision impaired. TheBraille display consists of a row of cells for displaying individualtext characters. According to the invention, a rotary navigation wheelis located adjacent an end of the row of Braille cells and, preferably,a separate rotary navigation wheel is located adjacent each end of therow of Braille cells for navigating through text. The navigation wheelsmay be aligned with the axis of the row of Braille cells, or,preferably, located above or below the axis of the row of Braille cells.By offsetting the navigation wheels form the axis of the row of Braillecells, the user may continuously read displayed text without risk thatthe hand which is reading will bump into the navigation wheels.

[0017] Referring to the drawings, FIG. 1 is a top plan view of anexemplary notetaker 10 having a Braille keyboard 11, a 20 cell Brailledisplay 12, and two speakers 13. The Braille display 12 has an axis 14.The notetaker 10 includes a program controller in the form of a computerand a digital memory for storing text data entered through the keyboard11 and for causing the Braille display 12 to display the stored data oneline at a time. The notetaker 10 also can include known software forconverting the stored text to speech for driving the speakers 13.Notetakers 10 of this type are commercially available products commonlyused by blind and low vision users.

[0018] According to the invention, a first navigation wheel 15 accordingto the invention is positioned adjacent to the left end of the Brailledisplay 12 and above the axis 14, and a second navigation wheel 16 ispositioned adjacent to the right end of the Braille display 12 and abovethe axis 14. Alternately, the navigation wheels 15 and 16 may beadjacent the ends of the Braille display 12 aligned on the axis 14, orbelow the axis 14. It should be appreciated that the notetaker 10 may beconstructed with a different number of Braille cells in the display 12,and that the keyboard 11 may have different configurations or may be aconventional QUERTY keyboard. It also should be appreciated that only asingle navigation wheel 15 or 16 may be provided and that its positionmay be varied to meet the needs of users of the notetaker 10.

[0019] As shown in FIGS. 1 and 2, the navigation wheel 15 is attached toan encoder 17 and is mounted to project through the top surface 18 of ahousing 19 for the notetaker 10 or other text device. The navigationwheel may be, for example, a commercially available edge drive jogencoder, such as a type EVQWK encoder manufactured by Panasonic. Thewheel 16 will be attached to a similar encoder (not shown). It will beappreciated that other commercially available encoders also may be usedwith the navigation wheels 15 and 16.

[0020] The exemplary encoder 17 has 3 switched outputs, as shown inFIGS. 2 and 3. A switch 25 is located between a common terminal 26 andan “A” terminal 27 and a switch 28 is located between the commonterminal 26 and a “B” terminal 29. A switch 30 is located between twoterminals 31 and 32. The switch 30 is actuated by depressing the wheel15.

[0021] Preferably, each incremental position of the wheel 15 has apositive mechanical detent that can be felt by the user to providefeedback as to how far the displayed text or a cursor is moved. As anavigation wheel 15, 16 is rotated, a series of pulses are produced bythe encoder, as shown in FIG. 4. Preferably, one pulse is produced foreach detent. The pulses are produced by opening and closing the twoswitches 25 and 28. In the exemplary encoder, a two phase quadratureoutput is produced with 15 pulses per revolution. The output of theswitch 25 is represented by the line 33 and the output of the switch 28is represented by the line 34. The wheel detents position the wheel 15at steady points 35, depending on the position of the wheel 15. Thenumber of pulses per revolution may vary with the application. Byproviding a two phase quadrature output, information on the direction ofrotation is provided in addition to the number of increments ofrotation.

[0022] The navigation wheel is intended to be used in conjunction with arefreshable Braille display to facilitate navigation through text. Inaddition to use with a refreshable Braille display, the navigation wheelmay be used with other text products for the visually impaired, such aswith a personal digital assistant (PDA), with a portable computer, orwith a Braille or speech output device such as reading machines andnotetakers. The navigation wheel is designed to provide a means for avision impaired user to rapidly scroll through a document or a dialogbox stored in the computer's memory. The computer may be programmed sothat rotation of the navigation wheel by one increment advances thedisplayed or spoken text or a cursor, for example, by one character, byone word, by one line of displayed text, by one paragraph, or by onepage. By depressing the navigation wheel, the programmed operation modeof the navigation wheel may be changed. Where the computer or deviceconnected to the navigation wheel produces synthesized speech, each timethe mode is changed by depressing the wheel, the computer may beprogrammed to announce the newly selected mode. For example, if thenavigation wheel is programmed in a mode for advancing the text by onedisplayed line of text per increment, pressing the wheel may switch to amode where each increment advances by one paragraph. In response to thewheel depression, the computer may announce “paragraph”. Then as thewheel is rotated, the text product may be programmed to announce thenumber of the paragraph in the text which is being displayed.Alternately, the text product may generate a tone which indicates theposition in the text. The text product also may be programmed to audiblyannounce the selected location in the text, such as announcing thenumber of a selected paragraph or page, or announcing a word which isselected. For example, if the text product has the bible stored in itsmemory, the navigation wheel may be programmed for scrolling by line,chapter or verse, and the desired type of scrolling is selected bydepressing the navigation wheel.

[0023] When two navigation wheels are provided, the computer may beprogrammed so that the second navigation wheel operates in the same modeas the first navigation wheel, or in a different mode. For example, anavigation wheel located to the right of the row of Braille cells may beprogrammed to advance the text by one displayed line. When the readerreaches the end of the displayed line of text, a simple rotation of thewheel adjacent the end of the line of cells by one increment willadvance the displayed text to the next line. Rotation of one incrementin a reverse direction moves the displayed text back by one line. Anavigation wheel located to the left of the row of Braille cells may beprogrammed to select the displayed paragraph, or to move the cursor to aspecific word in the displayed line so that the displayed text can beeasily edited. Where the cursor is moved from word to word in thedisplayed text, the word selected by the cursor may be announced by thecomputer to further facilitate rapid navigation through the text by thevision impaired user. For each navigation wheel, the direction ofrotation of the wheel determines the direction of movement through thedocument. Feedback to the user is provided through the Braille display,through audio tones, and/or through synthesized speech.

[0024] By providing separate navigation wheels at the opposite ends ofthe Braille display, the reading speed may be greatly increased. Theuser may use one hand for continuous reading the Braille display and theother hand for continuous document navigation. Consequently, the handused for reading does not have to be removed from the Braille cells.Further, the Braille display may be read by either right handed or lefthanded users. This permits the Braille reader to increase his or herreading speed compared to existing devices and to scan a list much morequickly.

[0025] The programmed function of the switch operated by depressing thenavigation wheel also may be varied. In one mode, depressing thenavigation wheel may cause the product to say the current word. Inanother mode, the line and column number may be announced in response todepressing the navigation wheel, or the current word may be selected forediting.

[0026] The navigation wheels are an advance over prior products for useby the blind in navigating through text since they provide users bothincremental and rapid scrolling capability. Navigation by keyboard canbe quite slow, since it requires use of both hands. This is a seriousdisadvantage to a Braille user who must remove his hand from the Brailledisplay to type on the keyboard and then return to the Braille displayto read the new information. The additional function provided bypressing the wheel allows the user to take action at the currentlocation without removing his or her hand from the wheel. The navigationwheel also is superior to a slider which cannot provide the infiniterange of movement afforded by the navigation wheel.

[0027] It will be appreciated that various modifications and changes maybe made to the above described preferred embodiment of a navigation aidfor a refreshable Braille display without departing from the scope ofthe following claims.

1. In a refreshable Braille display including a plurality of refreshableBraille cells mounted in a row in a housing for reading by a user movinga finger along said row of cells between opposite ends of said row, theimprovement comprising an encoder mounted in said housing adjacent oneend of said row, a rotatable wheel associated with said encoder forcausing said encoder to generate at least one pulse each time said wheelis rotated a predetermined increment, and a programmable controlleradapted to operate said Braille cells to display text and to scroll thedisplayed text by a predetermined increment in response to said at leastone pulse when said wheel is rotated through an increment.
 2. Therefreshable Braille display of claim 1, and wherein said encoderproduces two out of phase pulse signals as said wheel is incrementallyrotated, and wherein said programmable controller is adapted to scrolltext displayed on said Braille cells in one direction when said wheel isrotated in one direction and is adapted to scroll text displayed on saidBraille cells in an opposite direction when said wheel is rotated in anopposite direction.
 3. The refreshable Braille display of claim 2, andwherein said rotatable wheel includes a plurality of detents which canbe felt by a user each time said wheel is rotated through apredetermined increment.
 4. The refreshable Braille display of claim 3,and further including a second rotatable wheel and a second encodermounted at an end of said row of Braille cells opposite said one end. 5.The refreshable Braille display of claim 4, and wherein each of saidencoders include a switch which is actuated by depressing the wheelassociated with said encoder, and wherein said programmable controlleris responsive to actuation of an encoder switch to change the incrementin which text is scrolled in response to said at least one pulse fromsuch encoder.
 6. The refreshable Braille display of claim 5, and whereinsaid programmable controller is a notetaker including a programcontrolled computer having a memory, and a keyboard for entering textdata into said memory.
 7. A refreshable Braille display comprising aplurality of Braille cells arranges in a row and adapted to display aline of text, an encoder located adjacent an end of said row of cells, arotatable navigation wheel connected to said encoder, said encoder beingadapted to generate pulses when said navigation wheel is rotated, andmeans for scrolling text displayed on said Braille cells in response torotation of said navigation wheel.
 8. A refreshable Braille displayaccording to claim 7, and wherein said navigation wheel has a pluralityof detents which can be felt by a user when said navigation wheel isrotated through a predetermined increment, and wherein said encodergenerates a predetermined pulse pattern when said navigation wheel isrotated through said predetermined increment.
 9. A refreshable Brailledisplay according to claim 8, and wherein encoder generates a firstpredetermined pulse pattern when said navigation wheel is rotated in onedirection through a predetermined increment and a second predeterminedpulse pattern when said navigation wheel is rotated in an oppositedirection through a predetermined increment.
 10. A refreshable Brailledisplay according to claim 7, and further including a second encoderlocated adjacent an opposite end of said row of cells, a secondrotatable navigation wheel connected to said second encoder, said secondencoder being adapted to generate pulses when said navigation wheel isrotated, and wherein means also scrolls text displayed on said Braillecells in response to rotation of said second navigation wheel.